K'nex Grenade
This is a working K'nex grenade I threw together with instructions, so you can explode it too!
Pieces You Need
The Base
Build this and add a white connecter over the top and another arm in mirror on the other side like in the second photo. Then, add a white rod to the bottom and an orange connector to the rod.
The Release Mechanism
Put the yellow rod into the orange connecter and then thread on the yellow hemisphere and put on the black stopper.
Loading
The shrapnel (six spacers) on the arms and put the hemisphere over them. Finally, put the orange connecter on the top of the yellow rod to act as a safety pin and stretch two loom bands (or just a normal band doubled up) in the holes in each arm.